Webs and methods of making same

ABSTRACT

There are disclosed methods of making RFID transponder webs and intermediate webs such as RFID strap webs and antenna webs, as well as such webs per se.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of pending application Ser.No. 11/116,014 filed Apr. 27, 2005 of James R. Kline, Richard K. Bauerand Rudolph J. Klein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to methods of making webs including antenna websand RFID transponder webs and to RFID antenna webs.

2. Brief Description of the Prior Art

The following prior art is made of record: U.S. Pat. No. 4,910,499 andpublished U.S. Patent Application 2004/0215350A1.

In the field of radio frequency identification (RFID) to which thisinvention relates, an RFID chip is connected to an antenna to form atransponder into which data can be written and from which data can beread. It is known to make labels, tags, business forms, packaging andthe like which incorporate such transponders. The chips are very smalland require connection to antennas. To facilitate this connection,straps including chips are connected to the antennas. A strap includesan RFID chip and a pair of strap contacts or connecting elements used toconnect the chip to an antenna. It is common to provide the straps in awide web, wherein the straps are arranged close to each other inparallel columns and transversely extending rows. These wide strap webshave some residual adhesive on their electrically conductive sideresulting from the manufacturing process and accordingly these widestrap webs are co-wound with an adhesive. The straps have a high densityalong and across the web. In order to use the narrow webs of straps, thestraps must eventually be separated as by cutting them from the narrowstrap web prior to connection to antennas. Alternately, an electricallyconductive tape can be co-wound with the strap web.

It is known to use an electrically conductive thermoset adhesive film tointerconnect flexible circuits to printed circuit boards or otherflexible circuits. Conductive particles loaded into the adhesive allowinterconnection through the adhesive thickness but are spaced far enoughapart to be electrically insulating in the plane of the adhesive.

SUMMARY OF THE INVENTION

The invention relates to improved methods of making RFID transponderwebs and intermediate webs such as patterned adhesive webs and antennawebs.

The invention relates to the methods of making webs of antennas. Oneembodiment of the method involves providing a composite antenna webhaving a first carrier web and a second carrier web between which aretransverse rows of first and second antennas, wherein the first antennasare adhesively adhered to the first carrier web and the second antennasare adhesively adhered to the second carrier web, and delaminating thefirst and second carrier webs from each other to provide first andsecond antenna webs, and thereafter slitting the first wide antenna webinto narrow first antenna webs each having a single column of firstantennas and slitting the second wide antenna web into narrow secondantenna webs each having a single column of second antennas.

It is preferred to form the antennas by providing a web of a flexibleelectrically conductive metal, forming slots in the metal web alonglongitudinally extending columns and lateral rows, and cutting the metalweb generally transversely into rows of side-by-side antennas.

According to an improved method of making antenna webs, there isprovided a composite antenna web having a first carrier web and a secondcarrier web between which are transverse rows of alternate first andsecond antennas, the first antennas being adhesively adhered to thefirst carrier web and the second antennas being adhesively adhered tothe second carrier web, separating the first and second carrier websfrom each other to provide first and second antenna webs, and thereafterslitting the first antenna web into narrow first antenna webs eachhaving a single column of antennas and slitting the second antenna webinto narrow second antenna webs each having a single column of antennas.

As an intermediate to the making of antenna webs, a longitudinallyextending carrier web is provided, and applying a patterned adhesivecoating to the carrier web in transversely extending rows or linescorresponding in shape generally similar to rows of first antennasspaced by non-adhesive or non-tacky areas corresponding in shapegenerally similar to rows of transversely offset second antennas andscrap.

As an intermediate to the making of antenna webs, a longitudinallyextending carrier web is provided, and applying a patterned adhesivecoating to the carrier web in transversely extending rows or lines in ashape generally similar to rows of second antennas and scrap spaced bynon-adhesive or non-tacky areas corresponding in shape generally similarto rows of transversely offset first antennas.

The invention includes a method of making a transponder web whichincludes providing a web of antennas, passing the antenna web partiallyaround a heated first drum, providing a web of RFID straps, separatingthe straps one-by-one from the strap web, applying the straps one-by-oneto a heated, vacuum, second drum, moving the heated drums to bring thestraps and the antenna web together to connect the straps to theantennas to provide a web of RFID transponders.

The invention also relates to an antenna web including a flexible web ofelectrically conductive metal, slots in the metal web alonglongitudinally extending columns and lateral rows, and the metal webbeing cut generally transversely into slotted antennas.

The invention also relates to an antenna web including a flexible,electrically conductive metal web cut into longitudinally extendingcolumns with alternate end-to-end first and second rows of side-by-sidefirst antennas and side-by-side second antennas, a first film adhered tothe first antennas of the first rows, and a second film adhesivelyadhered to the second antennas of the second rows.

The invention also relates to a web including a longitudinally extendingcarrier web, a patterned adhesive coating on the carrier web havinglongitudinally spaced adhesive areas with non-linear or cascading orvariable transversely extending edges in transversely extending rowslongitudinally spaced apart by rows of non-adhesive or non-tacky areas,and wherein the adhesive areas and the non-adhesive or non-tacky areasare similar in shape but are laterally offset with respect to eachother.

In a specific embodiment, a composite RFID strap web includes a wide webof RFID straps in longitudinally extending columns and transverselyextending rows, and a conductive adhesive web comprising a flexiblecarrier web, a release coating on one side of the carrier web, athermoplastic conductive adhesive web releasably adhered to the releasecoating, the adhesive being adhered to all the straps in the wide strapweb, and the adhesive coating containing electrically conductiveparticles. The resultant composite wide strap web can be slit intonarrow strap webs. A specific embodiment of a method of making narrowcomposite RFID strap webs includes providing a wide web of RFID strapsin longitudinally extending columns along the wide web and intransversely extending rows across the wide web, providing a wide web ofthermoplastic adhesive containing electrically conductive particles,adhering the wide web of adhesive to the wide strap web to provide awide composite strap web by heating the adhesive sufficiently to adherethe adhesive to the wide strap web, and slitting the wide compositestrap web longitudinally into narrow composite strap webs. Strapsbearing the adhesive can be cut from a narrow strap web and the methodincludes electrically connecting the straps to antennas to providetransponders. The adhesive can comprise a heat seal adhesive. The strapand the antenna are positioned for attachment under pressure and theadhesive on the strap is heated at a sufficient temperature to connectthe strap to the antenna.

BRIEF DESCRIPTION OF THE DIAGRAMMATIC DRAWINGS

FIG. 1 is a perspective view of a web of RFID transponders in roll formmade in accordance with methods of the invention;

FIG. 2 is an enlarged, fragmentary, top plan view of the transponderweb;

FIG. 3 is a fragmentary top plan view of a wide RFID strap web;

FIG. 4 is a fragmentary sectional view taken generally along line 4-4 ofFIG. 3;

FIG. 5 is a flow chart depicting the making of a narrow, one columnwide, composite RFID strap web from a wide RFID strap web having columnsand rows of RFID straps;

FIG. 6 is a perspective view showing the conversion of a wide web ofRFID straps into a plurality of narrow composite webs of RFID straps;

FIG. 7 is a top plan view of one of the webs of narrow (one-up)composite RFID straps shown in FIG. 6;

FIG. 8 is a perspective view showing a method of making webs of antennasfor use in making RFID transponders;

FIG. 9 is a top plan view taken generally along line 9-9 of FIG. 8showing slots or cutouts that have been cut into a web of a flexible,electrically conductive metal;

FIG. 10 is a top plan of a first carrier web taken generally along line10-10 of FIG. 8 showing a pattern of an adhesive coating on a firstcarrier web in accordance with the invention;

FIG. 11 is a fragmentary top plan view taken generally along line 11-11of FIG. 8 showing the slotted metal web and the underlying carrier webwith its patterned adhesive;

FIG. 12 is a fragmentary top plan view taken generally along line 12-12of FIG. 8 showing the slotted metal web having been cut into rows offirst and second antennas;

FIG. 13 is a top plan view of a second carrier web taken generally alongline 13-13 of FIG. 8 showing a pattern of an adhesive coating on asecond carrier web in accordance with the invention;

FIG. 14 is a fragmentary side elevational view of a composite antennaweb taken along line 14-14 of FIG. 8;

FIG. 15 is a view taken generally along line 15-15 of FIG. 8 showing thefirst and second carrier webs being separated together with theirrespective first and second antennas;

FIG. 16 is a perspective view of the first wide antenna web being slitinto narrow antenna webs;

FIG. 17 is a perspective view of the second wide antenna web being slitinto narrow antenna webs and trimmed of waste or scrap;

FIG. 18 is a flow chart depicting the method illustrated in FIGS. 8through 17;

FIG. 19 is a perspective view depicting a method of making an RFIDtransponder web from webs of RFID straps and antennas;

FIG. 20 is an enlarged, fragmentary, perspective view of a cutter and anapplicator also shown in FIG. 19;

FIG. 21 is flow chart depicting the method of FIG. 19 of the invention;

FIG. 22 is a perspective view depicting an alternative method of makingan RFID transponder web from webs of RFID straps and antennas;

FIG. 23 is a flow chart depicting certain steps of the methodillustrated in FIG. 22;

FIG. 24 is a perspective view of a composite adhesive web in accordancewith the invention;

FIG. 25 is a diagrammatic side elevational view illustrating themanufacture of the composite adhesive web shown in FIG. 24;

FIG. 26 is a perspective view showing a wide strap web being adhered tothe composite adhesive web shown in FIGS. 24 and 25 to provide a widecomposite strap web followed by slitting into narrow composite strapwebs; and

FIG. 27 is a side elevational view illustrating the bonding of straps toantennas on a carrier web.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to FIG. 1, there is shown a roll R of a web W of radiofrequency identification (RFID) transponders T. The web W includes acarrier web CW on which the transponders T are carried. The roll Rtypically has a core 25 or a coreless central opening by which the rollR can be mounted for rotation.

With reference to FIG. 2, one RFID transponder T on the left side ofFIG. 2 is shown in greater detail. Each transponder T is comprised of anantenna A and a strap S having an RFID chip C. No strap S is shown onthe antenna A on the right side of FIG. 2 for clarity. The antennas Aare generally bow-tie shaped, but they can have other shapes. Theantenna A has a slot 26 shown to have a generally T-shapedconfiguration. The top or horizontal part 27 of the slot 26 and a stemor vertical part 28 of the slot 26 define a pair of contacts orattachment elements 29 to which a strap S can be attached.

FIG. 3 illustrates a wide strap web WSW of RFID straps S on a carrierweb 31 comprised of flexible plastics film. The web 31 is common to allthe straps S. The straps S are arranged in columns C1 through CN androws R1, R2, R3 and so forth. Commercially available strap webs WSW asdepicted in FIG. 3 can be purchased with multiple columns of straps Sacross the strap web.

FIG. 4 shows the construction of one form of strap S. The strap S has anon-electrically conductive plastics film or carrier 31 with a recess 32for receiving an RFID chip C as shown. Covering the film 31 is anon-electrically conductive plastics film 34 having a pair of holes 35for each strap S. A suitable conductor such as electrically conductivesilver printing 36 is applied over the film 34 and the silver printing36 passes into the holes 35 in contact with connections on the chip C.Following application of the printing 36, the printing 36 hardens. Theprinting 36 is large enough in area so it can easily form contacts orcontact elements 37. The upper surface of the contacts 37 as shown inFIG. 4 is the electrically conductive side of the strap S and the lowersurface 31′ of the non-conductive film 31 is the non-electricallyconductive side of the strap S. The straps S have their contacts 37facing upwardly as viewed in FIGS. 3 and 4.

It is inconvenient to attempt to apply straps S to antennas A while thestraps S are in a wide web having columns of straps S. With reference toFIG. 5, it is preferred to start with a commercially available roll of awide web of straps having columns and rows of closely spaced straps eachwith an electrically conductive side as seen at block 39. The wide strapweb WSW is unwound from a roll and the conductive side of the straps isexposed. Next, the wide strap web WSW is provided with a coating overthe transponder straps S with a material which not only has adhesiveproperties and is therefore referred to as an adhesive 40 shown in FIGS.6 and 7, and this adhesive 40 also contains electrically conductivemetal particles 41 shown by stippling in FIGS. 6 and 7. The adhesive 40may or may not be tacky. For clarity, the straps S are shown in solidlines in FIGS. 6 and 7 even though the straps S are beneath the adhesive40. Although it is possible to selectively coat only contacts 37 of thestraps S using a patterned adhesive, it is preferred to coat the entirestrap web WSW with the conductive particle-containing adhesive 40. Theadhesive 40 is preferably an anisotropic adhesive. The coating of thestrap web WSW is shown at block 42 in FIGS. 6 and 7. Next, if theadhesive 40 is tacky, a release liner 43 (FIGS. 6 and 7) having arelease coating such as silicone is laminated into contact with theadhesive 40. The adhesive 40 is against and between the release-coatedside of the liner 43 and the conductive side of the contacts 37 toprovide a wide composite strap web CSW as depicted in block 44. Next, asshown at block 45 the wide web CSW is slit into narrow composite strapwebs NCSW. Thereafter, the narrow composite strap webs NCSW are woundinto rolls as indicated at block 46 for future use in makingtransponders.

FIG. 6 shows the wide strap web WSW as being unwound from a roll 47 andmoved into cooperation with an adhesive coating head 48 supplied with aheat seal adhesive through a conduit 49. The coating head 48 preferablyapplies a uniform continuous coating or layer of the conductiveparticle-containing adhesive 40 to the surface of the strap web WSW. Inthat the conductive side of the contacts 37 face upwardly as viewed inFIG. 6, the adhesive 40 and the particles 41 it contains are in directcontact with the contacts 37. A roll 50 of release liner 43 with itssilicone-coated side on the outside of the roll 50, is passed partiallyaround a laminating roll 52 to effect lamination of the coated strap webWSW. The resulting composite strap web CSW passes between rolls 52 and53. Downstream of the rolls 52 and 53, the composite strap web CSW isslit into a plurality of narrow composite strap webs NCSW having asingle column of straps S (or one-up) by knives 51, and rewound intorolls 54, 55 and 56. Although only three-wide rows of transponder strapsS are illustrated, strap webs having any desired number of straps perrow can be provided, coated, slit and rewound.

FIG. 7 shows a narrow composite strap web NCSW with its liner 43 brokenaway to show the straps S coated with the adhesive 40 containingconductive particles 41.

With reference to FIG. 8, there is illustrated a method of makingantenna webs. The starting material is a roll 57 of a flexibleelectrically conductive metal web 58 which is unwound and passed tobetween a punch roll 59 and a die roll 60. The web 58 is preferablycomprised of aluminum. The punch roll 59 and die roll 60 cooperate topunch out slots AT from the metal web 58 in a pattern best shown inFIGS. 9, 11 and 12. The roll 60 can be a vacuum roll by which metalchads (not shown) resulting from the punch out operation can be removed.Simultaneously with movement of the web 58 to the punch roll 59 and thecooperating die roll 60, a web 61 of a flexible transparent plasticmaterial is paid out of a roll 62 and passed between a patterned roll 63and a back-up roll 64. The web 58 is referred to for convenience as a“first web”. The pattered roll 63 coats or prints a pattern of anultraviolet (UV) curable adhesive A′ (FIG. 11) onto the upper surface ofthe web 61 according to a pattern illustrated in greater detail in FIG.10. The conductive web 58 which has been slotted and the web 61 arelaminated together as they pass between rolls 65 and 66. Thus, thelamination occurs downstream of the place the slots AT are made in theweb 58. The combined webs 58 and 61 are shown in greater detail in FIG.11. From there, these combined webs 58 and 61 pass overran ultraviolet(UV) light source 67 which cures the UV-curable adhesive A′ on the web61 applied by the roll 63. Once cured, the adhesive A′ is dry andnon-tacky. Next the combined webs with the cured adhesive A′ holdingthem together pass between a cutter roll 68 having cutting blades 69 anda plain back-up roll 70. The cutter blades 69 cut the web 58transversely along cascading non-linear lines or cuts 71 as best shownin FIG. 12 without cutting into the web 61. It is readily apparent thatthe slots AT and the cuts 71 together separate the web 58 into rows ofside-by-side and end-to-end antennas A. As the combined webs 58 and 61travel, a film or web 72 of flexible transparent plastics material isunwound from a supply roll 72′ and is passed between a pair of rolls 73and 74. The roll 73 is a patterned roll that coats or prints adhesive A′in a pattern best shown in FIG. 13 to the upper side of the web 72. Theweb 72 is then passed partially around a roll 75 and from therepartially around a roll 76. Combined webs 58, 61 and 72 referred to asAW pass between the roll 76 and a back up roll 77 and from there theypass beneath an ultraviolet (UV) light source 67′. The webs 61 and 72being transparent or sufficiently so that the UV light can readily curethe adhesive A′.

FIG. 14 is a side view of the sandwich or composite web AW comprised ofthe patterned adhesive-coated webs 61 and 72 and the intervening slottedand cut conductive metal web 58.

From there, the combined webs 58, 61 and 72 pass beneath an ultravioletlight source 78 which cures the adhesive A′ on the web 72. From there,the combined webs 58, 61 and 72 pass between a pair of rolls 79 and 80,and from there the webs 61 and 72 pass in the directions of arrows 89and 90 and are wound into rolls 91 and 92.

With reference to FIG. 9, the left-hand portion 83 of the conductive web58 shows the unslotted web as it comes off the roll 57. When the web 58passes between the punch roll 59 and the die roll 60 the slots AT areformed in the web 58. The slots AT extend in laterally spaced columns inpatterns that alternate from column-to-column. The slots AT of the outercolumns and the slots AT of every other column between the outer columnsextend in the same direction. Intervening or alternate columns of slotsAT extend in the opposite direction. The metal chads (not shown) removedby the punch roll 59 and the die roll 60 are T-shaped and, therefore,all of the conductive material within the periphery of each slot AT isremoved. Each slot AT is comprised of the horizontal cut out 27 (FIG. 2)and a long vertical cut out 84. Together the slot portions 27 and 84form the slots AT depicted in FIG. 9.

FIG. 10 depicts the pattered adhesive A′ applied by the roll 63 (FIG. 8)to the first web 61. The two rows of zones or areas 85 of adhesive A′are shown to be identical in shape. The non-adhesive or non-tacky zonesor areas 86 between the adhesive areas 85 are similar but not identicalin size and shape to the areas 85 as will be seen and described withreference to FIG. 12. The areas 86 are laterally offset from the areas85 as is also seen in FIGS. 11 and 12.

FIG. 11 shows the relationship of the slots AT through the conductiveweb 58 to the adhesive A′ on the web 61. The left side of FIG. 11 showsthe adhesive A′ by broken lines because the adhesive on that side ofFIG. 11 is beneath the conductive web 58.

FIG. 12 shows that the adhesive A′ has non-linear edges 85′ spacedinwardly from the non-linear lateral edges 71 of the antennas A, as ispreferred. It is to be noted that the slots AT and the cuts 71 defineantennas A and waste or scrap SC. In the illustrated composite antennaweb of FIG. 12, first rows 1st have three antennas A and second rows 2ndhave two antennas A and scrap SC. Even though the wide web shown in FIG.12 is only three antennas wide in rows 1st, the scrap amounts to only asmall portion of the overall web, the greater the number of antennasacross the web the less the percentage of scrap SC to the overall amountof metal material in the web 58. It is noted that the number of antennasA in the first rows 1st is greater than the number of antennas A in thesecond rows 2nd. Generally, the numbers of first antennas A will exceedthe number of second antennas A by one, thus first row 1st is shown tohave three antennas A and second row 2nd is shown to have two antennasA.

FIG. 13 shows the pattern of adhesive A′ in the web 72 for registrationwith the second antennas A of the conductive web 58. Adhesive zones 87(FIG. 13) are identical to adhesive zones 85 (FIG. 11), and non-adhesiveor non-tacky zones 88 (FIG. 13) are identical to non-adhesive ornon-tacky zones 86 (FIG. 11).

With reference to FIGS. 10, 11 and 13, it is apparent that the areas 85and 87 of adhesive A′ have the same size and shape. The areas 85 and 87are continuous as is preferred, yet they are referred to as “rows”.There are shown three antennas A over each area 85. Similarly, there areshown two antennas A and two pieces of scrap SC under each area 87. Soeven though the areas 85 and 87 are considered rows, each row 85corresponds to three antennas A, and each row 87 corresponds to twoantennas A and two pieces of scrap SC. Each adhesive area 85 isconsidered to include adhesive area sections 85(1), 85(2) and 85(3),shown to be identical to each other, and each area section 85(1), 85(2)and 85(3) corresponds to and underlies an antenna A and adhesivelysecures the web 61 to one of the antennas A in row 1 ^(st). Eachadhesive area 87 includes adhesive sections 87(1), 87(2) and 87(3) shownto be identical to each other and identical in size and shape toadhesive sections 85(1), 85(2) and 85(3). However, the sections 85(1),85(2) and 85(3) are in row 1 ^(st), and the sections 87(1), 87(2) and87(3) are in row 2 ^(nd). The rows 2 ^(nd) of adhesive A′ can also beconsidered to have adhesive sections 87(A) which have generally theshape as the antennas A and areas 87(SC) which have generally the shapeas the scrap SC. The adhesive sections 87(A) adhesively secure theantennas A in row 2 ^(nd) to the web 72 and the adhesive sections 87(SC)adhesively secure the scrap SC in row 2 ^(nd) to the web 72. Thus,although the adhesive areas 85 and 87 have the same appearance, theadhesive sections 87(1), 87(2) and 87(3) on the web 61 are laterallyoffset or staggered with respect to adhesive sections 87(A). By havingthe antennas A in row 1 ^(st) offset or staggered from the antennas A inrow 2 ^(nd) there is no waste of the metal web 58 between antennas A inthe end-to-end antennas of rows 1 ^(st) and 2 ^(nd), except for waste SCthat occurs only at the marginal sides of the web AW at every otherantenna row.

With reference to FIGS. 8 and 15, the first antenna web AW1 to which thefirst antennas A are adhesively adhered passes in the direction of arrow89 following separation and the second antenna web AW2 to which secondantennas A are adhesively adhered passes in the direction of arrow 90following separation. From there the first web AW1 is rewound into aroll 91 and the second antenna web AW2 is rewound into a roll 92.

As shown in FIG. 16, the first wide antenna web roll AW1 is next slitinto three narrow antenna webs 61′ using slitter blades 93 from whichthe one-up or single antenna column wide, narrow antenna webs 61′ can bewound into narrow rolls 94, 95 and 96. The side edges of the web 61 canhave excess material which can be trimmed, if desired.

With reference to FIG. 17, the second wide antenna web roll AW2 is slitby knife 97 into narrow antenna webs 99 and 100 and trimmed by knives 98to remove waste or scrap SC, and thereafter wound into narrow antennaweb rolls 101 and 102.

FIG. 18 is a simplified flow chart depicting a method according to theinvention of making transponder webs. In block 103, a flexible,conductive metal web is provided as a starting material. Next as shownin block 104, antennas are partially formed by partially cutting themetal web at first and second rows. Also, a wide first plastic film webis provided as another starting material as indicated at block 105. Atthe same time as the antennas A are partially formed at block 104, anadhesive pattern of adhesive areas 85 in first rows 1st is printed orcoated onto the first plastic web 61 for registration with the firstantenna rows 1st as indicated at block 106. Next, as depicted at block107, the metal web 58 with first partially cut antenna rows registeredwith first rows 1 ^(st) of adhesive A′ on the first plastic web 61 andthe web 61 are laminated to each other. The preferably UV curableadhesive A′ is then cured as depicted at block 108. Thereafter, themetal web 58 is cut into first and second rows of antennas A as depictedat block 109. While the webs 58 and 61 are moving or traveling, a wideroll of a second plastic film 72 provided at block 110 is printed withan adhesive pattern of rows 87 of adhesive A′ for registration withsecond antenna rows 2 ^(nd) as indicated at block 111. Next, the metalweb 58 and the second plastic web 72 are laminated on the side of themetal web 58 opposite the first plastic web 61 to provide a compositeantenna web AW per block 112. Thereafter, the UV curable adhesive A′ onthe web 72 is cured as indicated at block 113. Next the first and secondplastics webs 58 and 72 are separated to provide a first wide antennaweb AW1 with first antenna rows 1st and a second wide antenna web AW2with second antenna rows 2nd as per block 114. Next the first antennaweb AW1 is wound into a wide roll as depicted at block 115 and thesecond antenna web AW2 is wound with a wide roll as depicted at block116. Next, the first antenna web AW1 is slit into narrow antenna webs61′ one antenna wide or one-up and rewound into rolls 94, 95 and 96 asshown at block 117, and the second antenna web AW2 is slit into narrowantenna webs 99 and 100 one antenna wide or one-up and rewound intorolls 101 and 102 as shown at block 118. Because the antenna web AW2contains the scrap SC, it is preferred to trim the web AW2 of the scrapSC using outboard knives 98 as shown in FIG. 17. If desired, after block114, the first antenna web AW1 and the second antenna web AW2 can beslit and rewound without the steps indicated at blocks 115 and 116.

With reference to FIG. 19, the one-up linered strap web NCSW in a rollR′ is paid out and travels over a defective strap detector 119 whichattempts to read and/or write to the chip C in each strap S. The strapweb NCSW is advanced by feed roller 120 and 121, one of which ismotor-driven, and the strap web NCSW passes to a cutter and applicatorassembly 122 shown in greater detail in FIG. 20. The assembly 122includes a block 123 with a knife or cutter element 124 and anapplicator 125 in the form of a resilient elastomeric pad 125′. Theblock 123 is suitably actuated as by a piston/cylinder device, asolenoid, or the like indicated at 126 in FIG. 19. The knife or cutter124 cooperates with an inclined edge 127 of a knife or cutter blade 128so that the strap web NCSW is progressively cut laterally as the knives124 and 128 cooperate. The separated leading strap S is either appliedto a heated vacuum drum 129 by the descending action of the applicator125, or in the case of a defective strap S, the defective strap S isremoved by vacuum through a duct 130.

The drum 129 can be considered to be a transfer drum because ittransfers a separated strap S to the antenna web AW1 and applies a strapS to an antenna A. The illustrated first antenna web AW1 is paid out ofthe roll 94 for example and passes partially around a roll 131 andpartially around a heated drum 132 which can be a vacuum drum. The drums129 and 132 rotate at the same peripheral speed and the straps S areapplied precisely to the contacts 29 (FIG. 2) to form the transpondersT. It is noted that the conductive particle-containing adhesive 40 (FIG.7) heated by the heated drum 129 is activated. In addition, the heateddrum 132 heats the antennas A. When a strap S and an antenna A arebetween and in pressure contact with the drums 129 and 132 the contacts37 on the straps are electrically connected to the contacts 29 on theantenna, and the conductive particles 41 help make good contact. Thetransponder web W thus formed passes to a cooling surface of a coolingdrum 133 and from there is rewound into a roll R. It is preferred thatwhile the web W is wound into the roll R, a liner 134 is co-wound sothat each wrap of the web W is separated from the adjacent wrap by linermaterial. The web W can be wound transponder-side-in as shown in FIG. 19or transponder-side-out as shown in FIG. 1, as desired.

With reference to FIG. 21, there is shown a simplified flow chart of themethod of making a web of transponders depicted in FIGS. 19 and 20. Atblock 135 a one-up strap web NCSW is passed to an inspection station 119and at block 136 the leading straps S are separated on-by-one from thestrap web NCSW. Defective straps S are removed as they are separated bythe knives 124 and 128 through a duct 130 by the assistance of vacuum asindicated at block 137. The remaining straps S are progressively appliedto the first heated transfer drum 129 to which they are held as the drum129 rotates (counterclockwise in FIG. 19) until the leading strap S onthe drum 129 is in a position opposed to the drum 132 at which time thevacuum to that strap S is interrupted, as summarized at block 138. Whilethe transfer drum 129 is rotating, antenna web AW1 is passed partlyaround the heated drum 132 as indicated at block 139. The drum 129 movesto apply straps S to the antennas on the second drum to form atransponder web W as shown at block 140. Next the web W preferablypasses partly around a cooling drum to cool the transponder web W asshown at block 141. It is preferred to optionally apply a liner 134along the entire surface of the transponder web W as indicated at block142 and to wind the linered transponder web W into a roll R as indicatedat block 143.

It should be noted in FIG. 15 in particular that the slots 26 in theantennas A of web AW1 extend in the opposite direction from the slots 26in the antennas A of web AW2, although the antennas A per se of each webAW1 and AW2 are identical. Accordingly, in the event it is desired touse the antenna web AW2 in the arrangement of FIG. 19, the registrationof the straps S and the antenna web AW2 should be adjusted so that thecontacts 37 on the straps S meet the contacts 29 on the antennas A.Alternatively, the antenna web AW2 needs to be rewound again beforeloading it into the position occupied by the roll 94 in FIG. 19 so thatthe web AW2 can be used the same way the web AW1 is used in FIG. 19.

In the embodiment of FIG. 22 the same reference characters are used todesignate identical components having the same construction andfunction. The differences in the embodiment of FIG. 22 over theembodiment of FIGS. 19 and 20 are as follows in this paragraph:Referring to FIG. 22, roll R″ is comprised of a narrow strap web USWwhich may have been slit from a wide strap web as shown if FIG. 3. Theweb USW does not have any adhesive coating like the coating of adhesive40 shown in FIGS. 6 and 7. The strap web USW is feed to the defectivestrap detector station 119 to the cutting station where the straps S areseparated on-by-one from the strap web USW. Defective straps S areremoved through the duct 130 and acceptable straps S are transferred tothe drum 129. The web AW1 is paid out of roll 94 for example passedpartially around the roll 131 and partially around the heated drum 132.An adhesive applicator head 144 supplied with adhesive through a conduit145 applies an electrically conductive particle-containing, heatsoftenable and heat curable adhesive 146 to the contacts 29 on theantennas A. When the straps S adhered by vacuum to the transfer drum 129are applied in registration to the antennas A, the contacts 37 on thestraps are electrically connected to the contacts 29 on the antennas A,thereby forming transponders T. The heat from the drum 132 softens andcures the adhesive 146. After the straps S have been connected to theweb AW1, the web AW1 becomes a transponder web W which is then passedpartially about the cooling surface of the cooling drum 133. The web Wis then passed beneath a printing transponder detector 146 which readsand/or writes to each transponder T and prints a mark on or near adefective transponder T. From there, the web W is wound into a roll R.

FIG. 23 is a simplified flow chart illustrating mainly the differencesin the embodiment of FIG. 22 over the embodiment of FIGS. 19 through 21.As in the embodiment of FIGS. 19 through 21, FIG. 23 shows that antennaweb AW1 is passed partly around heated drum 129 at block 148 and anuncoated one-up strap web USW is passed to a defective strap detectionstation at block 149. Adhesive 146 is applied to the antennas A forconnection to the straps S as indicated at block 150. After the good andthe bad or defective straps S are separated from the strap web USW andapplied to the heated transfer drum 129 as indicated at block 151, thestraps S are connected to the antennas A using heat and pressure appliedto the conductive adhesive 146 as indicated at block 152. The antennas Aand straps S continue to be heated so long as the web W is in contactwith the drum 132. From there the web W is passed to a cooling drum 133.From there, all the transponders are tested by writing to and/or readingfrom each transponder T at a defective transponder detection station 147as the web W moves, and a mark is printed on the transponder web W at ornear the defective transponders T. Next the transponder web W is woundinto a roll R.

It is apparent that when registering the various webs 58, 61, 72, NCSW,USW, AW1 and AW2 registration marks can be provided on these webs.

It is apparent that instead of using antenna webs AW1 and AW2 in themethods depicted in FIGS. 19 through 23, the antenna webs can instead bemade by other and different methods utilizing printing, etching,deposition, and so on.

By example, not limitation, the wide strap webs WSW are available fromAlien Technology Corporation, Morgan Hill, Calif. under Model No.ALC-140-AS, and the overall dimensions of each strap Sx is 3.5 mm by 7mm by 0.2 mm thick. The plastics film webs 61 and 72 of plasticsmaterial are available from Multi-Plastics Corporation, Mount Pleasant,S.C., and are transparent and known in the trade as Mylar preferably ofthe heat stabilized version known as Type LCF-4000. This plastics filmis comprised of clear polyester and has a thickness of 0.05 mm. Theconductive metal web 58 is comprised of aluminum having a thickness of0.012 mm and its 457 mm wide. The adhesive 40 is a product of ForboAdhesives Corporation, Durham, N.C., a subsidiary of Forbo InternationalS.A, Zurich Switzerland, type Swift heat seal adhesive #82681 mixed withabout five percent by weight of Ames Goldsmith Corporation, Glens Falls,N.Y., type LCP15 0.015 mm diameter silver particles. The ultravioletcurable adhesive A′ is a product of RAD-CURE Corp., Fairfield, N.J.,known under the designation TYPE X 4002138B. The conductive adhesive 146is a product of Emerson & Cuming Corp., Billericz, Mass., a NationalStarch & Chemical Company, Bridgewater, N.J., and is sold under theformula XCA-90216.

With reference to FIG. 24, there is shown a roll RA of a compositeadhesive web CA comprised of a carrier web 200 having a release coating201 on at least a first side and in the event the composite conductiveadhesive web CA is to be wound into a roll as shown there is preferablyalso a release coating 202 on a second side of the carrier web 200. Therelease coatings 201 and 202 are shown by light stippling in FIG. 24.The release coatings 201 and 202 can be comprised of silicone or anyother suitable material such as a wax. A web of electrically conductiveadhesive 203 is in contact with the release coating 201 and is shown byheavier stippling in FIGS. 24 through 26. The electrically conductiveadhesive web 203 is comprised of a thermoplastic adhesive containingelectrically conductive particles described in further detail below.

FIG. 25 illustrates a method of making the composite adhesive web shownin FIG. 24. Coating heads 204 and 205 apply a preferably curable releasecoating such as silicone to the carrier web 200. Curing of the releasecoating in the case of silicone occurs at UV heaters 206 and 207. As therelease coated web 200 moves in the direction of arrow 208 a coatinghead 209 applies a coating of the thermoplastic, electrically-conductiveparticle containing adhesive 203 to the release coating 201 to form thecomposite electrically conductive adhesive web CA.

FIG. 26 illustrates a web of RFID straps S, namely, a wide strap web WSWas shown in FIG. 3 in a roll WSWR. The composite conductive adhesive webCA moves in the direction of arrow 210 and is brought together orcombined with wide strap web WSW as the web CA passes about roll 211.The roll 211 is preferably a heated roll which causes the thermoplasticadhesive of the conductive adhesive web to adhere to the conductive sideof the RFID straps S of the wide strap web WSW. If desired, the roll 211need not be a heated roll but the thermoplastic adhesive 203 can beheated by a roll (not shown) or other suitable heater downstream of theplace where the webs WSW and CA are combined. Therefore, the adhering ofthe adhesive 203 of the web CA to the web WSW can be where these websare combined into layers or at difference places. The combined webs WSWand CA form a combined or composite strap web 212 which is considered tobe laminated once the adhesive component of the adhesive web 203 hasbeen heated to a temperature sufficient to adhere the adhesive web 203to the strap web WSW. From there, the composite web 212 can be slit byknives 213 into narrow strap webs 214, 215 and 216 and wound into narrowcomposite strap web rolls 214R, 215R and 216R. The strap webs 214, 215and 216 have only one column of straps S, as do the webs NCSW.

With reference to FIG. 27, there is shown an arrangement wherein strapsS, which were severed from the strap webs 214, 215 and/or 216, are heldto the drum 129 as by vacuum and brought into position with antennas Acarried on a web AW1 as also illustrated in FIGS. 19 and 20. The drum129 and a back-up drum 132 are preferably both heated and when the strapS is applied to the antenna A and heated to a temperature preferablyhigher than the temperature at which the adhesive 203 is adhered to theweb WSW and pressure is exerted on the strap S and the underlyingadhesive 203 by drums 129 and 132, the electrically conductive particlesin the layer of adhesive 203 electrically connect the strap S to theantenna A. The temperature at which the straps S are electricallyconnected to antennas A is higher than the temperature at which theadhesive web 203 is adhered to the straps S, but not so high as toadversely affect the straps S.

With respect to the embodiment of FIGS. 24 through 27, the wide strapwebs WSW are the same as described above, however the conductiveadhesive 203 differs from the adhesive 40. By way of example, notlimitation, the adhesive in the conductive adhesive 203 is a product ofBostik Findley, Inc. Wauwatosa, Wis., U.S.A. is of a type EVA-based hotmelt, thermoplastic adhesive No. H1477 mixed with 15% by weight ofPotters Industries, Inc., type SC500P18, 0.035 mm diameter silver coatedcopper particles.

Other embodiments and modifications of the invention will suggestthemselves to those skilled in the art, and all such of these as comewithin the spirit of this invention are included within its scope asbest defined by the appended claims.

1. Method of making narrow composite RFID strap webs, comprising:providing a wide strap web having RFID straps in longitudinallyextending columns along the wide strap web and in transversely extendingrows across the wide strap web, providing a wide, flexible, carrier webhaving opposite first and second sides wherein at least the first sideis coated with a release coating with thermoplastic adhesive appliedonto the release coating on the first side and wherein the releasecoating on the first side is between the carrier web and the adhesive toform a wide composite adhesive web, wherein the adhesive containselectrically conductive particles, laminating the wide compositeadhesive web to the wide strap web with the adhesive against the widestrap web to provide a wide composite strap web, and the adhesive beingheated sufficiently to adhere the adhesive to the wide strap web, andslitting the wide composite strap web longitudinally into narrowcomposite strap webs.
 2. Method as defined in claim 1, including:severing the straps from the narrow strap webs, and electricallyconnecting the straps to antennas to provide transponders.
 3. Method asdefined in claim 2, wherein the electrically connecting step includesheating the adhesive to a higher temperature than was used to adhere theadhesive to the wide strap web.
 4. Method as defined in claim 3, whereinpressure is used in electrically connecting the straps to the antennas.5. Method as defined in claim 1, wherein the conductive adhesivecomprises a heat seal adhesive.
 6. Method as defined in claim 1, whereinthe second side is coated with a release coating.
 7. Method as definedin claim 1, including wherein the second side is coated with a releasecoating, and winding the narrow composite strap webs into rolls.